In her first foray into nonfiction, The Shelf Unstable, the poet Elisa Gabbert turns her penetrating eye to the continental shelf. This otherworldly zone of the sea, at once familiar and alien, provides an unexpectedly rich backdrop for Gabbert's contemplative prose. As though adapting to her aquatic setting, Gabbert changes her pace from page to page, at times skipping lightly along the surface but frequently stopping to examine her surroundings in depth. But even when dwelling at length on a particular subject, like the very odd geoduck (pronounced gooey-duck) of the Pacific northwest, Gabbert is constantly adjusting her focus to take in the broader world (as when she shows how shifting Asian culinary tastes have changed the calculus of Seattle sea-farmers, or how delicate-seeming Japanese fishing floats have slipped from their nets and floated across the Pacific to wash up on Oregon's shores). The effect can be breathtaking but it can also be exhausting, as Gabbert juxtaposes slivers of the undersea world with pedestrian scenes from our lives, refusing to let the kaleidoscope rest, implicitly denying that there is such a thing as a simple story to be told. Inevitably, threads are dropped and fascinating themes are hinted at but never developed, and some readers will find the effect off-putting.

But in its second half, the book finds a persistent theme as Gabbert examines the geology of the continental plates that underlie the continental shelf. Here Gabbert flirts with a facile analogy to human experience as she describes the mechanical determinacy but radical day-to-day unpredictability of plate tectonics. But ultimately she pulls it off, her tone darkening as she hints at our powerlessness in the face of elemental forces we can barely understand. Particularly bleak is Gabbert's characterization of self-knowledge as a kind of willful deception, a narrative that we attach to a fundamentally aimless process of building up and eroding away, uplift and subduction.

But The Shelf Unstable constitutes an eloquent response to its own fatalism. Gabbert weaves a touching and deeply human story about the continental shelf. The verve with which she pulls it off suggests that perhaps the endeavor is not futile. The story, even if it cannot be meaningful in some ultimate sense, can at least be told with skill and nuance and a kind of terrible beauty.